1. Field of the Invention
This invention relates to flexible dispensing packages and, more particularly, to flexible dispensing packages having a self-supporting, stand-up configuration.
2. Prior Art
The packaging of liquid and dry products in heat sealable, dispensing enclosures by high-speed production techniques and equipment is a well-developed art. The heat sealed, packaged product is generally referred to as having a form-fill-seal construction and is sometimes characterized as a form and fill package. These packages may have a rectangular pouch configuration or other special shape and construction. As to the pouch configuration, there are three basic forms, which are known as the pillow type, three-side seal and four-side seal. The pillow type is constructed from one web and is provided with top and bottom seals and a vertical seam which can take the form of a fin seal or a lap seal. The three-side seal is constructed from one web and is provided with a fold along one side and seals along the remaining three sides. The four-side seal is constructed from one or two webs and is provided with bottom, side and top seals. The web used in the construction of heat sealable packages can take the form of a single layer or a multi-layer laminate. In either form, the oppositely disposed sealable faces comprise heat sealable thermoplastic material such as polyethylene, polypropylene or the like. In the laminate configuration, the inner layer is, for example, polyethylene and the outer layer can be cellophane, paper, polyester, metalized polyester, aluminum foil or the like. A heat sealable laminate comprising three or more layers is sometimes designated as a laminate having a sandwich construction or configuration.
The form and fill package, with a rectangular pouch configuration, is generally referred to as a lay flat or envelope package because neither the top nor the bottom nor either side provides a base for up-right support of the package and, therefore, when the package is placed on a horizontal surface either the front or rear panel of the package engages the horizontal surface in an ostensibly lay flat manner.
Although the form and fill, lay flat package provides significant production and economic benefits to the producer, a major disadvantage to the consumer arises when the package is opened and less than the total contents of the package are dispensed. When the partially empty and open, lay flat, package is placed on a horizontal surface, a significant portion of the remaining fluidic material can flow out of the package through the tear-open aperture.
The prior art has sought to overcome the spill-out characteristics of lay-flat packages and to provide stand-up, flexible packages analogous to bottles, cans and paperboard cartons by developing form and fill and related flexible packaging that incorporates a base which permits the package to stand up-right on a support surface.
U.S. Pat. No. 3,051,368 (W. S. Schneider, et al., 1962) discloses a flexible wall, dispensing container provided with a base that is defined by multiple edges lying in a common plane.
U.S. Pat. No. 3,387,701 (W. S. Schneider, et al., 1968) discloses a flexible wall, dispensing container incorporating a mechanically formed and thermally set flat base.
U.S. Re 27,302 (W. S. Schneider, et al., 1972) discloses a mechanical and thermal method for converting the lower, sealed end of a form and fill package to a flat base.
U.S. Pat. No. 3,432,986 (W. S. Schneider, et al., 1969) discloses a packaging machine of the form and fill type for producing a flexible wall, dispensing container incorporating a mechanically formed and thermally set flat base.
U.S. Pat. No. 3,354,601 (W. S. Schneider, et al., 1967) discloses a method for making a stand-up, flexible wall, dispensing container which includes the step of attaching a flexible tubular film to a base.
U.S. Pat. No. 3,380,646 (L. Doyen, et al., 1968) discloses a self-supporting pouch type container wherein the lower end portion of the container incorporates a gusset construction that diverges outwardly to form an elliptical product support base upon the addition of fluidic material to the container.
U.S. Design Pat. Nos. 200,553 (A. P. Corella, et al., 1965); 200,554 (A. P. Corella, et al., 1965); 205,635 (A. P. Corella, et al., 1966); and 208,272 (A. P. Corella, et al., 1967) disclose diverse designs for flexible wall, dispensing containers having flat bases.
The thin wall, flexible packaging of the prior art includes special folds and heat seals, developed by special purpose equipment, to provide a base for up-right support. It would, of course, be advantageous to provide a form and fill package which has stand-up capability, but which does not require special folds and heat seals for this purpose.